The guy who taught me how to squat and DL uses "spotters", but no hooks. When he squats he has people observe him, but not really in position, and he has them take the hooks out of the cage. My favorite line from him is "No hooks means no way out".

Look him up on youtube. Guy's name is Andy Ruse, but his youtube name is Blenderate. He's definitely a freak of nature. And the best part; he drives a smart car. Really nice guy though.

My wife is a high school teacher, and the football players she teaches told her that their coach doesn't let them use the safety bars in the power racks when they squat. There could never be a "reason" for that to be a good idea as far as I'm concerned.